Grinding mill



Jan. 16, '1940. R. 1.. SCHUHMANN GRINDING IILL Filed Oct. 51, 1936 2Sheets-Sheet 1 mmvmk Richard L. Sc/zuhmann BY ATTORNEYS! Jan. 16, 1940.

R. L. SCHUHMANN GRINDING nu,

Filed 001;. 31, 1936 2 Sheets-Sheet 2 Fig. 3

INVENTOR Richard l. Schuhmamz ATTORNEYS.

Patented Jan. 16, 1940 UNITED STATES PATENT OFFICE Application October31, 1.3, Serial No. 108,533

scum.

Coflee mills, having grinding elements that are manually adjustable toat least three different grinding positions corresponding to coarse,medium and fine grinds, are largely used in retail .3 stores andoperated by clerks who are supposed,

first, to determine what kind of grind the customer requires and,second, to set'the mill for such grind; In many instances, however, theclerks carelessly operate the mill on such previous setting as it maythen have, and, as a result, often produce grinds which are not suitedto the oilstomers requirements. To compel more individual attention onthe part of the clerks and thereby correspondingly reduce thepossibility of such careless operation, it has been proposed to providesuch mills with means which necessitate the resetting of the grindingelements for each separate grinding operation and which indicate to thecustomer, the position at which the grinding elements are set duringeach grinding operation. The'present invention is principally directed-to an improvement in such means.

The principal object of the invention is to provide a simple andeiifective means for preventing the removal of ground coffee from themill before it is reset to an inoperative position.

Another object is to provide a simple and eifective system for stoppingthe motor when the mill is set to an inoperative position, for startingthe motor when the mill is moved out of its inoperative position, andfor indicating to customers the operative setting to which it may bemoved, and to control the operation of such system automatically throughthe necessary movement of the setting means. I

The invention is illustrated in the accompanying drawings wherein:

Figure l is a side elevation of a mill which embodies the invention andwhich is set in a nongrinding position;

Figure 2 is an elevation of the opposite side thereof;

Figure 3 is a section through line H of Figure 1 with the lid omittedand with the mill set in a grinding position;

Figure 4 is a section through line H of Figure 3; and

Figures Band 6 are ditic views of the control system.

The invention, as illustrated, is applied to a coflce mill which isshaped externally to simulate the appearance of a well known form ofcoffee percolator. The casing comprises a base I, body 2 and lid 3. Thelid 3 covers an opening through whichcoffeebeansmaybeintroducedintoahopper I. The beans pass downwardly from the hopper l to the inner orrear face of an inner grinder element I and thence through an opening inthe element I into the grinding space between it and the outer grinderelement 6. The inner 5 grinder element 5 is fixedly mounted on asuitable frame within the body 2 of the casing while the outer grinderelement I is fixedly mounted on a rotatable shaft I which is arrangedfor longitudinal movement between inner and outer limits.

The shaft I extends from the outer element 6 inwardly through thecentral opening of the inner element I with its inner end connected tothedrlveshaftofamotortsoastoberotated 15 thereby, this connection beingslidable to permit longitudinal movement of the shaft. The lattercarries, directly behind the inner element 5, a pair of oppositelydisposed short blades 9 which operate, during rotation, to move thebeans through the opening of the grinder element 5 into the grindingspace. The shaft I also extends from the outer grinder element 6outwardly through a cover member I0 and projects outwardly from the hubthereof. The cover member II is removably secured to the casing in anysuitable manner and, when removed, permits the shaft I and grinderelement i to be inserted into or removed from the casing as a unit.

In the embodiment illustrated the shaft 1 normally occupies a positionadjacent the outer limit of movement which position is herein designatedas "off. In moving from the oil position toward the inner limit, theshaft I successively occupies, at spaced points, coarse, medium and finegrinding positions which are herein designated as "coarse boil", "mediumperc and "fine drip". The shaft I is normally urged longitudinallyoutward toward and held in the of! position by a spring II arrangedbetween it and the drive shaft of motor I. Its longitudinal inwardmovement to any of its other positions, may be effected in any suitablemanner. As shown, it is effected through the agency of a knob i2 whichis placed over the projecting outer end of shaft I and screw-threaded tothe outer peripheral face of the hub of cover member I I so as to moveinwardly and outwardly along the hub when angularly turned to the rightand left (see Figure 1). The knob I2 carries an adjusting screw it whichengages the end face of the shaft I in the oil position of both shaftand knob. Manifestly when the knob is turned from the 05'' to any othersetting it will move inwardly and thus effect a co inward movement ofthe positions by providing. it with a spring pressedbutton II to engagein suitable hub depressions which correspond in number and spacing tothe mill settings.

The operation of the mill, may of course, be controlled solely through amanually operable main line switch It in the motor circuit. With thepresent arrangement, however, it is desirable to stop the motorautomatically when the mill is set at the "oi!" position. Accordingly aconven tional automatically-closing push button control switch I1 isprovided in the motor circuit and mountedonthecasinginpositiontobedepressed' and held in its open position by the pointer il when thelatter is in its of! position and to close automatically and remainclosed when the pointer; is moved out of the "oi!" position. With acontrolswitchofthischaracterinthemotorcircuit,

operation of the motor will begin automatically when the pointer ismoved out of the oi! position and stop automatically when it is returnedthereto.

When the pointer I4 is moved from the "08" to a grinding or operativesetting, it is desirable to indicate, to a customer, the particularsetting to which it has been moved. To this end an indicator system isprovided having. for each operative setting, an automatically openingpush button switch il, II- or II and a lamp II to illuminate a window 2.which isvisible to the customer and. on or adjacent which the applicablesetting data is printed or otherwise indicated..

Each switch it", IF or II is mounted on the casing and operated bypointer It in a manner similar to motor control switch ll. Thus theswitch I, for the coarse boil setting, for example, is automaticallyclosed by the pointer when it reaches the coarse boil position andautomatically opened when it leaves such position. When clom, the switchcloses the circuit of'lamp II, which is mounted behind the coarse boilwindow 20, the circuitforeachsuchlampbeingacrossthe motor I. Naturallythe other switches II- and I. operate in a similar manner to energisetheir respective lamps II and thus elect the illumination of theirrespective indicator windows.

It may now be noted that ground coifee, discharged from the grindingspace, passes downwardly into a removable coifee receiving recep- 'tacle2i which is positioned underneath the.

grinding elements. This receptacle, in such coflee receiving position,projects partly into the interior ofthecasingthroughasideopeninginthebody thereof between base I and cover member IIand rests in such position on a shelf 22.

Now, in further accordance with the invention,

means are provided to preventthe removal of ground codes from the millbefore it is returned to the 08" position so as to compel its beingreset before another grinding operation can be carried out. While thismay be accomplished in various ways, it is herein accomplished in asimple,

and yet effective way y providing the knob i! with arr-extension Ila,which in the "oi!" posi- 'gised to operate said elements, a switch forention extends out of the path of movement of the receptacle to and fromcoifee receiving position and which in all other positioned the pointerextends into such path sufliciently to block the removal or replacementof the receptacle 2i. 5 With this arrangement it is necessary to set themill in the off position before the coifee receptacle can be removed orreplaced; hence resetting is rendered necessary between separategrinding operations.

Having described my invention, I claim:

1. Agrindingmillcomprlsingcooperatingand relatively adjustable grindingelements operable through a range of grinding positions, a controlmemberadaptedtobeshiftedbytheoperatorfor lladjustingtherelationofthegrindingelements,andareceptaclelocatedbelowandinapcsition to directlyreceive groundmaterial from the grinding elements, means for supporting thereceptacleinsaidpositiomandmeansonthecom' trol member and dependent uponadiustmmt of said member for locking the receptacle against removal inanyposition of-grinding adjustment.

2.1nagrindingmillhavingcoopentingand relatively adjustable grindingelements operable through a range of grinding positions, a manuallyoperable control member adapted to be moved by the operator foradjustingthe position of the grinding elements and for designating theparticulargrlnddesiredareceptaclelocatedbelowthegrlndingelementsinapositiontodirectiyreceive the ground material from the grindingelementaandmeansdependentupontheadjust-,mentofthecontrolmemberi'orlockingthereceptacleagainstremovalinallpositionsoigrindingadjustment.

3.1nagrindingmillhavinggflndingelements adjustablehrougharangeofgrindingpositicm,amanualcontrolmemberforadjustingthepoaitionofthegrindingelementaareceptaclefor.receiving the ground material, means for supporting the receptacle in aposition for receiving thegroimdmateriahandmeansonsaidcontml member anddependent upon adjustment of saidmemberforlockingthereceptacleagainstre-llmovalexoeptwhentheeontrolmemberismoved toanon-grinding position.-

4.Inagrlndingmillhavinggrindingelementsadiustabietbrougharangeofgrindingpositions,a control member for adjusting the position of so the grinding elements,a receptacle for receiving theground material andmeansfor supportingthereceptacleinapositiontoreceivesaidgrolmdmaterial, said control memberhaving a projecting portion adapted tolcck the receptacleagainstremovaiwheninsaidpositionandinanypositionof grinding adjustmentof the control menlber.

5.A grinding mill comprising cooperating grinding elements, a motoradapted when enerergizing the motor, a control member adapted to adjustthe grinding elements through a plurality of grinding positions and toactuate the switch whereby to open it and dcenergiae the motor when thecontrol member is moved to a nongrinding position, and to close theswitch and energise the motor when the control member is moved to anygrinding. position. a receptacle for receiving the ground coffee, andlocking means dependent upon adjustment of the control member forretaining the receptacle in all positions of grinding adjustment.

